Business Segment Information - Segment Assets (Detail) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total Assets	$ 679,595	$ 644,739
Total Goodwill and Intangibles	242,767	248,149
Operating Segments | Electronic Systems
Segment Reporting Information [Line Items]
Total Assets	419,331	405,743
Total Goodwill and Intangibles	215,191	219,872
Operating Segments | Structural Systems
Segment Reporting Information [Line Items]
Total Assets	245,724	220,993
Total Goodwill and Intangibles	27,576	28,277
Corporate Administration
Segment Reporting Information [Line Items]
Total Assets	$ 14,540	$ 18,003